Breast cancer is the most common cancer among women (excluding basal and squamous cell skin cancer) in the U.S. and is the second most common cause of cancer death among women. In the year 2007, the estimated new cases of breast cancer among women in the U.S. is 178,480 and the estimated death from breast cancer is 40,460 (1).
Neoadjuvant chemotherapy for breast cancer is the use of chemotherapy before definitive surgical therapy such as lumpectomy or mastectomy. Compared with adjuvant or postoperative chemotherapy, neoadjuvant chemotherapy allows higher rates of breast conservation without compromising overall survival (2). In addition, neoadjuvant chemotherapy permits a unique opportunity to observe and evaluate tumor response to treatment and therefore, serving as an in vivo chemosensitivity assay. This may allow the tailoring of treatment for individual patients based on their tumor response to a particular chemotherapy regimen (3-5). This may potentially enhance response and survival and at the same time reduce unnecessary toxicities.
Not only neoadjuvant chemotherapy does result in similar overall survival compared with adjuvant chemotherapy, it is also associated with less adverse toxicities (6). Compared with adjuvant chemotherapy, neoadjuvant chemotherapy is associated with significantly less infectious complications and cardiotoxicity (6). In addition, there is suggestive evidence that neoadjuvant chemotherapy may be superior to adjuvant chemotherapy on survival outcome (7). In contrast with adjuvant chemotherapy, there is currently no clear recommendation on neoadjuvant chemotherapy regimens. There is a need for improved therapies for cancer.